GraphQL: Add `protected` field to `BranchType`
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Currently in REST we can query if a branch is protected. In GraphQL, we can find this out as part of a merge request:
The closest thing I can find is under `MergeRequestType` `app/graphql/types/merge_request_type.rb`, you can query if the branch is protected. But `BranchType` doesn't list protected as a field.
field :source_branch_protected, GraphQL::Types::Boolean, null: false, calls_gitaly: true,
description: 'Indicates if the source branch is protected.'
Looks like it queries `app/models/protected_branch.rb` but the service takes in a single project and ref. I wonder if we can do it in bulk.
We should add this field to `BranchType` so a consumer can query many branches.
issue